fiducial marks

fiducial marks

Any marker built into an aerial camera that registers its image on an aerial photograph as a fixed reference mark in the form of an image is called a fiducial mark. These are usually four fiducial marks on a photograph and are used to define the principal point of the photograph. Their appearance on the image permits various calibrations, such as determination of the degree of enlargement needed to fit the picture to the rectification grids. Fiducial marks are also marks in any instrument that define the axes whose intersection fixes the principal point of a photograph and fulfills the requirements of interior orientation. These are also usually four in number. See collimating marks
References in periodicals archive ?
Nordson EFD vision-guided dispensing robots use fiducial marks to automatically offset the dispense program and compensate for slight shifts in workpiece orientation or location.
The basic idea is to create a non-reversal pattern with two or three fiducial marks on the board or panel.
Fiducial mark locations are reviewed and fiducial marks are added, as needed, to support component placement and flying probe testing.
Thus, for scanning aerial photographs, an A3 format is necessary, because fiducial marks have to be clearly visible performing inner orientation.
Up to three fiducial marks are selected in a learning procedure.
This low error probability system based in application of hyperbolic wavelet transforms and integrated circuits photo masks fiducial marks geometric moment features.
The chorobates was an elongated wooden platform, sometimes with a water-filled longitudinal groove, having plumb bobs on each end that were aligned with fiducial marks on the structure.
Raw images can also be copied so that you can insert such things as highlights, fiducial marks, and notes directly into the copy while preserving the original image.
Sampling for calculations of the average friction is restricted to the middle portions of each cycle, as indicated by fiducial marks.
ONE OF THE handy aspects of getting boards assembled at Screaming Circuits is we don't require fiducial marks for standard process boards.
If the used camera is calibrated, interior image orientation may be done by transforming the measured coordinates into a calibration system, defined by fiducial marks or residual crosses.